To form a color photographic image, three color photographic couplers, i.e. a yellow coupler, a magenta coupler, and a cyan coupler, are contained in light-sensitive layers, and after exposure to light they are processed with a color developer containing a color-developing agent. During this process, the oxidation product of an aromatic primary amine, and the couplers, undergo coupling reactions with each other, to give color-formed dyes. Generally, a standard process of processing silver halide color light-sensitive materials comprises a color-developing step of forming a color image, a desilvering step of eliminating developed silver and undeveloped silver, and a washing step and/or an image stabilizing step.
The above desilvering step of eliminating developed silver and undeveloped silver, silver halide, is carried out by reoxidizing developed silver with a bleaching agent and fixing with a silver halide solubilizing agent. The said desilvering can be performed by carrying out successively two separate steps, i.e. a step using a bleaching solution, and a step using a fixing solution, or by carrying out a single step using a single solution of a combination of a bleaching agent with a fixing agent. The solution used in the latter is generally called a bleach-fix (blix) solution. It is known that, as the silver bleaching agent in the above bleaching solution and bleach-fix solution, a variety of oxidizing agents are used, and in view of low toxicity and environmental safety, metal complex salts of organic acids, such as EDTA ferric complex salt, are usually used. The use of complex salts in a bleaching solution and a bleach-fix solution for color photography is described, for example, in U.S. Pat. No. 4,288,618.
However, when such a ferric complex salt is used as a bleaching agent for color photography, sometimes a cyan dye image having a satisfactory density cannot be obtained. This phenomenon is generally recognized as reduction fading (hereinafter referred to as blix fading), and it occurs due to the change of a cyan dye to a leuco dye in a bleaching solution or a bleach-fix solution. U.S. Pat. No. 4,591,548 points out that the cause of the change of a cyan dye to a leuco compound is attributed to the presence of ferrous ions in a bleaching solution or a bleach-fix solution.
On the other hand, although it has hitherto been attempted to shorten the processing time, the need for shortening the processing time has recently been further increased because of demands for a shortened time limit of the delivery of finished products, a decrease in work in laboratories, miniaturization of processing systems for small-scale laboratories, which are so-called mini-labs, simplification of operation of such processing systems, etc.
The shortening of time in a color-developing step can be attained by combining suitably, for example, use of a coupler high in coupling speed, use of a silver halide emulsion high in developing speed, use of a color developer high in development activity, and an increase in temperature of a color developer. T. H. James, "The Theory of the Photographic Process," Section 15, E. Bleach-Fix System (Macmillan Publishing Co., Inc.), describes that, to shorten the time in a desilvering step, it is effective to lower the pH of the bleaching solution or the bleach-fix solution. However, to lower the pH of a bleaching solution or a bleach-fix solution disadvantageously facilitates the above blix fading of a cyan dye.
As an attempt to overcome this reduction fading of a cyan dye, the following various approaches are suggested. For example, JP-A ("JP-A" means unexamined published Japanese patent application) No. 316857/1988 describes that reduction fading is reduced by using a certain hydroquinone or quinone derivative. Further, for example, JP-A Nos. 51136/1989 and 289840/1990 describe that the change of the cyan dye to a leuco dye is suppressed by using an aqueous latex of a polymer having a specified structure. U.S. Pat. Nos. 4,151,680, 4,374,922, and 4,591,546 describe a group of cyan couplers that are preferable for overcoming the foregoing problem.
The effect of some of above-mentioned prior art techniques is not satisfactory, and although others of the above-mentioned prior art techniques are recognized to have an effect, the effect is obtained at the cost of photographic properties, such as image preservability, or they have demerits, such as a harmful influence on the burden of pollution. Therefore a highly effective technique of preventing blix fading of a cyan dye without causing any harmful effects has been desired.